var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var logger = require('morgan');

var indexRouter = require('./routes/index');
var usersRouter = require('./routes/user');

var app = express();

// view引擎设置
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');

app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(bodyParser.json());
app.use(express.static(path.join(__dirname, 'public')));

app.all('*',function(req,res,next){
  // 设置允许跨域的域名,*代表允许任意域名跨域
  res.header('Access-Control-Allow-Origin','*');
  // 允许的header类型
  res.header('Access-Control-Allow-Headers','content-type');
  // 跨域允许的请求方式
  res.header('Access-Control-Allow-Methods','DELETE,PUT,POST,GET,OPTIONS');
  if(req.method.toLowerCase() == 'options')
      res.send(200); // 让options 尝试请求快速结束
  else
      next();
})

app.use('/', indexRouter);
app.use('/user', usersRouter);


// 捕获404并转发到错误处理程序
app.use(function(req, res, next) {
  next(createError(404));
});

// 错误处理程序
app.use(function(err, req, res, next) {
  // 设置局部变量，仅在开发中提供错误
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // 渲染错误页面
  res.status(err.status || 500);
  res.render('error');
});

module.exports = app;
